October 19, 2009

Twisty Puzzle Spending Spree

As you may recall from my second post, my mechanical puzzle obsession actually started with an order from ThinkGeek.com: I ordered a Legend of Zelda t-shirt and decided to buy a few Hanayamas, which kicked off this whole wild ride into the land of the mechanical puzzle people. Anyways, I follow ThinkGeek's RSS feed for new items and items that are on sale, and they were having a sale on V-Cube 7's for $45, which was a good price for them as far as I could tell.

So I decided this would be a good time to give one a try and test whether or not I could generalize my knowledge about 3x3x3 to solve a 7x7x7. While I was there, I noticed that ThinkGeek had a few other twisty puzzles that were pretty reasonably priced too, so I ended up buying Megaminx, Rubik's Mirror Blocks Cube, and a knockoff Square-1 named Irregular IQ Cube. I thought that I might as well confront my fear of twisty puzzles head on! I guess I am kind of a sucker for a sale, and it worked just like retailers hope: the sale brought me in and I ended up buying more than I expected. And, to top it off, the V-Cube 7 is still on 'sale' months later!

When my puzzles arrived the first one I started with was Mirror Blocks, because I thought that it would be just like a 3x3x3, but somewhat harder to tell what the hell was going on. It is a really remarkable puzzle: nice smooth action, and it looks amazing when scrambled, like a piece of modern art. It is quite cool how the seams still line up no matter which way you turn the cube, which is somewhat baffling at first.

After toying around with it for a bit, I gave it a good scramble and tried to solve it. It is quite daunting once it is scrambled up and took me a while to get oriented. I decided to use the thinnest side as the bottom and work my way up. I studied the proportions of the pieces carefully as I made each move, and eventually was able to reassemble the cube. What fun! I scrambled and solved it a few more times just because it was that cool.

Next I tried the Square-1 knockoff. This was a very cheaply made puzzle: in fact, they send you two for the price of one! That was a good thing, because the stickers were falling off one of them like crazy. I glued them back on and worked on the second one while the first one was drying. This was quite disappointing though after my great experience with Mirror Blocks. The puzzle did not turn smoothly and jammed quite easily, but at least it was only $10 for the two of them. You get what you pay for!

This puzzle was quite baffling to me. I had trouble even getting it back into a square shape, much less getting the colors back on the right faces. I was able to get it back to a square and partly solved, but then I got stuck.  I worked on it for a few more days and haven't really spent much time on it since. I think if I had a better version I would be more likely to play with it, but fighting this one as it jams isn't a lot of fun. I'll probably buy an actual Square-1 in a while and see if I can figure it out.

After I had given up on the Square-1 for a while, I turned to Megaminx. I had no idea how difficult it would be, but thought that I could probably figure it out. The ThinkGeek Megaminx is not very good quality, it jams quite easily, which is unfortunate. This made it a bit tricky to scramble because of the number of faces and the frequency of the jamming, but eventually I got it mixed up pretty well.

I picked a random face to be the bottom and started to work my way toward the top. It was quite a challenge, especially with the large number of colors and I frequently screwed up and messed something up that I had previously solved. Eventually I figured it out though, I think it probably took me about two hours. The hardest part is getting the final pieces in place, because you need to do it without messing everything else up. I tried a bunch of moves and eventually found one that was similar to a 3x3x3 move that I used for a similar purpose, and it ended up working. Nice!

Finally, I tried to conquer the 7x7x7 V-Cube 7. This is a really daunting puzzle if you're not a twisty puzzle nut: just the sheer number of cubies is ridiculous. I played around with it for a bit, making patterns and whatnot. The action is very smooth, which was a delight after playing around with the cheaper twisty puzzles. It is definitely worth the extra few bucks to get a decent twisty puzzle: cheapo ones are a pain in the butt.

Eventually I decided to go for it and scrambled it up. If it looks daunting when solved, it was even more so when scrambled. I decided that my strategy was going to be solving the faces first, then the edges, then the corners. I worked my way from the center of each face outward in concentric squares, getting the 3x3 solved on each face before proceeding to get the 5x5 square solved and so forth. This took me a very long time. I didn't time myself, but it was probably 3-4 hours. I developed a little set of moves that would cycle three pieces between adjacent faces that worked pretty well, but it took a very long time to position each piece individually.

Next, I moved on to the edges, which weren't too hard...at first. Once I got to the end, I realized that my move was a 3-cyle and I need a 2-cycle to finish! (A move that would switch two edge pieces). Try as I might, I couldn't find a move that would break the 2-cycle. I kept ending up with other configurations that just reduced to a 2-cycle. Eventually by trying a move similar to a 3x3x3 move that is a two cycle, I managed to get the edges in a state where they could be solved by my 3-cycle move. I think this whole process took me about a week of working on it for an hour or two per day. Needless to say, I was quite satisfied when I finally figured it out.

Now came the easy part! With the edges solved and the faces solved, I could treat it just like a normal 3x3x3 cube. Needless to say, I was very careful, but after a few minutes I had it back to the solved state! I was quite pleased with myself!

That said, I haven't tried to replicate this feat since I have solved it. Writing this makes me remember how repetitive it was! I think it would be just as satisfying and interesting to do a 5x5x5 and it would take quite a bit less time. If you know how to do a 5x5x5, you pretty much can do a 7x7x7, so if I had it to do over again I might just do that instead. Still, it is kind of cool to say I have solved the 7x7x7!

You  might note that I didn't mention the 6x6x6, that's because my understanding is that even cubes are somewhat different from odd cubes because there is a parity problem that can occur. This seemed like an added annoyance that I would rather not deal with, which is why I haven't bothered with even cubes other than the Triple 2x2x2 I blogged about a few days ago.

Whew! I didn't think I was going to be able to get this entry done in a single night, but I was on a roll. Hope you enjoy it! Tomorrow I'll write about some more Karakuri boxes!

4 comments:

  1. Wow, good job on the 7x7x7. I have not yet tackled mine.
    I wanted to recommend mefferts.com as a source for twisty puzzles. Their stuff is pretty good quality, and their prices aren't bad (all their stuff is licensed and everything has free shipping). The site can be slow and function poorly, but they have a lot of good puzzles.
    The "Meffert's Puzzles" section has most of the good stuff- the Holey Megaminx (no center) is a nice piece of engineering, and the "4D8" is like a simple Alexander's Star that actually turns reasonably well.
    The Master Pyramorphinx has a very nice smooth mechanism, and the MorphEgg is also a great design (nicer than the Fisher's Golden Egg, in my opinion). I think the solid white or red MorphEgg is probably harder due to having fewer clues.

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  2. Thanks for the tip, Brett! I had run across Mefferts when I was thinking about upgrading to a decent Square-1, but didn't end up ordering yet. I'm sure I'll get to it eventually! How hard are the puzzles you mentioned? I'd like to start easy and work my way up. The Eggs look completely baffling!

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  3. I have a V-Cube too but I am afraid to mess it up. Excellent job solving yours. I have seen a movie of one being taken apart and that is not something you want to approach lightly either.

    I have a lot of unsolved puzzles sitting around my collection. Often I grow bored or frustrated and one year later they are still unsolved. Sounds like you are much more focused in your efforts! But have you solved the Yak yet?

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  4. Thanks George! If you can do a 3x3x3, the V-7 isn't too much harder, just repetitive. The edges can be a bit tricky at the end, though.

    Yeah, I am pretty driven when it comes to completing unsolved puzzles. I have two that I haven't solved yet, Square-1 and the Yak. I'll be posting about this in a day or so, but I did end up getting the Whale and that gave me a bit of an idea for what needed to be done on the Yak, but I haven't been able to do it yet. Someday!

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